[s-cars] An interesting FMIC "fact" (?)

[QSHIPQ at aol.com]

A couple things to consider here gentleman.  First, audi's stock IC's are 
*extremely* efficient for their size.  This means exactly that Bigger IC's in 
terms of HP gains will be more in tune with the turbo sizing/efficiency/output 
than actual IC.  Again, if one was to measure the audi IC pressure and temps pre 
and post core, you will find an efficiency in the 72-85% range (RS2 goodies 
attached), which means if you put on the biggest monster, best designed IC, a 
gain of 15% IC efficiency translates into a less than 15% HP gain.  

Offsetting a change in IC, will be the change in design.  If you are using a 
really good IC design (audi's do), then any design changes might very well be 
offset by a bit less efficient core construction, or better put, optimizing 
the design of given construction may yield no or worse results in measure.  It 
makes perfect sense to me Dave.  It's the nature of tradeoffs in really well 
designed IC's.

Before I'd even pick a design, get a baseline and get a target.  I'm pretty 
convinced that what MLP and Hap have done to their engine VE required that ASW 
change the design of the IC because of the amount of flow required dictated 
that they do so.  I certainly give ASW credit for achieving the right goals 
(flow and efficiency increase), but I question the 'automatic bigger is better' 
that some of you are following.   2 thermocouples, 2 pressure guages boys.

I say get these 4 probes installed and post those numbers.  I've seen plenty 
of theory and speculation here.  I've seen even theoretical price breaks 
bantered.  I think you all need to take a time out on this discussion and get some 
hard and fast numbers, then quite possibly one could put the price, benefit 
and design targets into clear perspective.

I argue, you just might find that what you have is gonna show that 'better' 
is not so easy.  Nor may you find all the 'gains' when the stock audi part is 
pretty darn good.  Then maybe, 2000USD may be better spent elsewhere first?

HTH

Scott Justusson
QSHIPQ Performance Tuning

In a message dated 2/26/2004 11:39:51 PM Central Standard Time, 
Djdawson2 at aol.com writes:
In a message dated 2/26/04 10:25:10 PM Mountain Standard Time, 
forgied at direct.ca writes:

> Frontal
> area: This is a rapidly decreasing function. If the proper core size is
> used, then doubling it will definitely not double the efficiency. More
> likely, doubling the core would raise the efficiency about 5% and cost
> twice the  necessary amount and add substantially to the weight.
> 

Yep, right on all accounts.  Those are exactly the points that seem to 
indicate a top to bottom core with more rows than you can get using a side to 
side 
makes more sense.  The odd thing is that ASW's testing seems to indicate that 
that rule of thumb isn't applying too well in practice.  That doesn't make 
sense to me.
Dave